The subject matter herein relates generally to battery modules.
Battery modules, such as those for electric vehicles or hybrid vehicles, typically includes a plurality of cells grouped together to form the battery modules. The battery modules are connected together to form battery packs. Each of the cells includes positive and negative cell terminals that are electrically connected together. Different types of battery modules are formed using different types of cells. For example, one type of battery modules are known as pouch type battery modules, another type of battery modules are known as prismatic battery modules, and a third type of battery modules are known as cylindrical battery modules.
Prismatic battery modules use prismatic battery cells that are stacked together. The positive terminals are aluminum and the negative terminals are copper. The positive and negative cell terminals have either threaded bores or threaded studs that receive threaded screws or threaded nuts, respectively, for terminating buss bars thereto. The buss bars are plates with two openings that are placed over adjacent positive and negative terminals. When using the threaded studs, the threaded studs pass through the openings and the threaded nuts are tightened to the threaded studs. The studs are typically steel studs that are screwed into the positive and negative terminals. When using the threaded screws, the openings in the buss bars are aligned with the threaded bores of the positive and negative terminals and then the threaded screws are loaded through the openings and tightened in the threaded bores. Both mounting techniques require a threaded connection to both the positive terminal and to the negative terminal. Tightening of the threaded nut or the threaded screw is time consuming, particularly since a typical battery module includes ten or more cells, thus having twenty or more nuts or screws to tighten. Tightening of the threaded nut or the threaded screw may cause over torque, under torque and/or cross threading. The over torque may damage the internal components of the cell and affect cell performance.
A need remains for battery modules that may be assembled quickly and reliably. A need remains for battery modules having terminals and buss bars that may be connected in an efficient manner.